The goal of this clinical trial is to learn if a culturally adapted Relapse Prevention Module (RPM-08) can reduce relapse risk in people with substance use disorders in Pakistan. The study also examines whether the adapted intervention is effective over time.

The main questions it aims to answer are:

Does the adapted RPM-08 reduce relapse risk compared to usual treatment? Are the effects of the intervention maintained after a follow-up period?

Researchers compared participants who received the adapted RPM-08 along with usual treatment to those who received usual treatment only to see if the intervention improves relapse outcomes.

Participants will:

Attend eight structured group sessions over eight weeks Receive usual treatment provided by the rehabilitation center Complete questionnaires at baseline, after the intervention, and at follow-up

This study employed a sequential exploratory mixed-method design integrating qualitative and quantitative phases. The qualitative phase focused on the cultural adaptation of the Relapse Prevention Module (RPM-08) using the ADAPT-ITT framework and Bernal's Ecological Validity Model to ensure cultural and contextual appropriateness for individuals with substance use disorders in Pakistan.

The adaptation process involved expert consultation, iterative refinement, forward-backward translation procedures, and pilot testing to establish linguistic clarity, cultural relevance, and clinical applicability of the intervention.

The quantitative phase utilized a non-randomized two-group pretest-posttest quasi-experimental design with a follow-up component. Participants were recruited using purposive sampling from a residential rehabilitation setting in Punjab, Pakistan. Eligible participants included male individuals diagnosed with moderate substance use disorder who were clinically stable and able to participate in group-based intervention sessions.

Participants were allocated into experimental and control groups within the treatment setting. The experimental group received the adapted RPM-08 intervention in addition to Treatment-As-Usual (TAU), while the control group received TAU only. TAU consisted of standard rehabilitation services including medical care, counselling, and psychosocial support.

The adapted intervention was delivered as a structured group-based program consisting of eight sessions based on cognitive-behavioral relapse prevention principles. The sessions focused on relapse awareness, coping strategies, identification of high-risk situations, and development of relapse prevention plans, with culturally relevant modifications incorporated into content and delivery.

Data were collected at multiple time points to examine changes over time and differences between groups. Statistical analyses were conducted using appropriate non-parametric tests and covariance-based methods to evaluate intervention effects while accounting for baseline differences and relevant covariates.

This study was registered retrospectively after completion of data collection.

Inclusion Criteria:

• Male participants diagnosed with moderate substance use disorder (DSM-5-TR)
• Aged 17 to 56 years
• Currently enrolled in a residential rehabilitation program
• Medically and psychologically stable to participate in group sessions
• Able to provide informed consent

Exclusion Criteria:

• Individuals diagnosed with severe psychiatric disorders (e.g., bipolar disorder, psychotic depression)
• Individuals with cognitive impairments affecting participation
• Individuals currently undergoing detoxification or taking medications that may influence treatment outcomes

Individual participant data will not be shared due to confidentiality and ethical considerations related to sensitive patient information. Data may be available from the principal investigator upon reasonable request for academic purposes.

This study was conducted as an open-label trial with no masking. Participants, care providers, and investigators were aware of group assignments due to the nature of the behavioral intervention.